I recently mentioned how I install NordVPN at the system level under Aurora using Blue Build: Installing NordVPN via BlueBuild
It was actually wanting a “normal” Emacs that got me to look into making a custom distro, because Flatpak seemed like it caused a lot of issues, and the Homebrew version (at least for Linux) is terminal-only.
Anyway, using Blue Build you could have a custom distro with Emacs in about an hour, and you can easily add new things to it as you learn more. The post I linked above includes multiple links to my GitHub repo, but for Emacs all it took was adding it to the package list in the template’s “recipe” file.